Answer:
The correct answer is B.
Explanation:
Given there is a hybrid produced between two species Rana Ridibunda and Rana Lessonae and their offspring can not reproduce, this can mean there is "Postzygotic Isolation" between the said two species. Postzygotic Isolation is defined as "not being able to have fertile offspring" and that is the case in the example. I hope this answer helps.
Enzymes act as catalysts that remain unmodified as they increase the rate of a chemical reaction.
Answer A:
1. Spiral chloroplast:
This organelle help in photosynthesis, because it contain green pigment called chlorophyll in which water and carbon dioxide combine in the presences of sun light to prepare glucose.
2. Cell wall:
It is chemically composed of<span> an outer layer of pectin and an inner layer of cellulose. It provide rigidity and shape to spirogyra cell.</span>
Answer B:
The other parts which are not labelled include mucilage, cytoplasm, pyrenoids, cytoplasmic strand.
Answer C:
Function of pyrenoid:
<span>Each chloroplast strand has several round bodies called 'pyrenoids', which are responsible for starch production.
</span>Function of mucilage:
Mucilage help in retaining water in cell.